presents
"Quantum data compression,
or how to Quantum WinZip"
speaker:
Dr. John A. Vaccarro
School of Computer Science
University of Hertfordshire
3 March 2004 (Wednesday)
Lecture Theatre LC108
Hatfield Campus
3 - 4 pm
Coffee/tea and biscuits will be available.
Everyone is Welcome to Attend
[Space Permitting]
Abstract:
Data compression is central to information theory. Messages typically contain redundant data and compression involves removing these redundancies. The information content of a message is given by its minimum compressed size (e.g. in bits). This underpins the bit as a unit of information content. In the quantum regime, messages consist of quantum letters. The quantum information content is likewise given by its minimum compressed size, and the corresponding unit of quantum information is a qubit. In this talk I will introduce the elements of Quantum Information Theory and review a few important data security protocols. I will then review the compression of classical messages (Shannon's coding) and the quantum counterpart, quantum data compression (Schumacher's quantum coding). I will end with a description of the first experimental demonstration of quantum data compression. This work was performed in collaboration with the Communication Research Laboratory, Japan and is the subject of a patent application. We demonstrate the compression of messages of 3 quantum letters into 2 qubits, and subsequently recover the original message.